Achieving Efficiency and Fairness in 802.11-Based Vehicle-to-Infrastructure Communications

An efficient medium access control (MAC) protocol should yield maximum throughput and fairness. However, because these two performance metrics have conflicting interests, an effective solution must address the trade-off between them. In this paper, we study the performance of the IEEE 802.11p MAC protocol in vehicle-to-infrastructure communications. The main focus is the trade-off between the system throughput and the level of fairness among the communicating nodes, which leads to a customized optimization problem. Accordingly, we formulate a multiobjective optimization problem to optimize both throughput and fairness, and propose a dynamic mechanism to maintain fairness among the mobile nodes. The optimization problem is solved by means of an approximate numerical solution, the results of which demonstrate the effectiveness of the proposed MAC scheme in terms of throughput and short-/long-term fairness.